Sewing machine drive



May 23, 1961 J. D. LANDEROS SEWING MACHINE DRIVE 2 Sheets-Sheet 1 FiledMarch 21, 1958 Jose 0. Landeros 1N VEN TOR.

Mae/4 3a. BY MM 22% y 23, 1961 J. D. LANDEROS 2,985,270

SEWING MACHINE DRIVE Filed March 21, 1958 2 Sheets-Sheet 2 Jose 0.Landeros 1N VEN TOR.

nite States Patent SEWING MACHINE DRIVE Jose D. Landeros, 541 1 S. MainSt., Los Angeles, Calif.

Filed Mar. 21, 1958, Ser. No. 722,926

14 Claims. (Cl. 19211) This invention relates in general to new anduseful improvements in sewing machine construction, and morespecifically to an improved drive for sewing machines.

At the present time substantially all sewing machines are powered byelectric motors. These motors are controlled either by means of arheostat or by means of a clutch. However, the present controls are suchthat not only is the starting and stopping of the sewing machine slow,which prevents accurate control of the sewing operation, but also it isdifiicult for the operator of the sewing machine to obtain the desiredspeed.

It is therefore the primary object of this invention to provide animproved drive for sewing machines, the drive being of such a naturethat the driving of the sewing machine is instantaneous upon theactuation of a control and at the same time the stopping of the drive ofthe sewing machine is instantaneous upon the releasing of the control.

Another object of this invention is to provide an improved sewingmachine drive, the sewing machine drive being of such a nature that thespeed of the sewing machine may be varied as desired by controlling thepressure exerted upon a foot pedal, the foot pedal controlling theengagement of the drive belt With a drive pulley and permittingcontinuous slippage between the drive spulley and drive belt, asdesired.

Another object of this invention is to provide an improved drive forsewing machines, the drive being of a relatively simple constructionwhereby the manufacture thereof is economically feasible, and at thesame time the drive being of such a nature that it may be readilymounted on existing and new machines with a minimum of modification.

A further object of this invention is to provide an improved drive forsewing machines, the drive including an idler pulley disposed remotefrom a driven pulley of the sewing machine, there being disposedintermediate the idler pulley and the driven pulley a drive pulley, thesizes of the driven pulley and the idler pulley relative to the drivepulley being such that the drive belt engaged over the driven pulley andthe idler pulley normally is disposed closely adjacent to, but out ofengagement with,

the drive pulley, there being provided suitable control means for movingthe drive belt into frictional engagement with the drive pulley wherebya relative driving and slipping action occurs so that the pressureexerted upon the drive belt may be used to vary the speed with which thedriven pulley is driven from the drive pulley.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout and in which:

Figure 1 is a fragmentary elevational view of a conventional type ofsewing machine employing the drive which is the subject of thisinvention;

Patented May 23, 1961 Figure 2 is a fragmentary end view of the sewingmachine of Figure l and shows further the relationship-of the variouscomponents of the invention with respect to the sewing machine; c

Figure 3 is an enlarged fragmentary vertical sectional view takensubstantially upon the plane indicated by the section line 3-3 of Figure2 and shows the specific mounting of the drive and a majority of thecomponents thereof; a

Figure 4 is an enlarged fragmentary vertical sectional view takensubstantially upon the plane indicated by the section line 44 of Figure3 and shows further the details of a brake of the drive;

Figure 5 is a fragmentary vertical sectional view taken substantiallyupon the plane indicated by'the section line 55 of Figure 1 and showsthe relationship between the idler pulley, the drive pulley, the drivebelt and a belt tightening roller;

Figure 6 is a fragmentary exploded perspective View showing the detailsof a support'for' the drive and a spacing shim; and

Figure 7 is an enlarged exploded perspective view showing the cammembers for effecting the release of the brake.

Referring now to the drawings in detail, it will be seen that there isillustrated in Figures 1 and 2 a conventional sewing machine assemblywhich is referred to in general by the reference numeral 10. The sewingmachine assembly 10 includes a'bench ortable 12 which is supported bysuitable legs' 14. Mounted on the top surface of the bench 12 is aconventional sewing machine unit which is referred to in general by thereference numeral 16. Among other conventional components, the sewingmachine unit 16 includes a balance wheel 18 to which there is attached adriven pulley 20.

Secured to the underside of the bench 12 rearwardly of the sewingmachine unit 16, as is best illustrated in V Figure 2, is a drive unitin the form of an electric motor 22. The electric motor 22 includes abase 24 which is secured to the underside of the bench 12 by means ofbolts 26. The electric motor 22 also includes an armature shaft 28 whichcarries a drive pulley 30. The drive pulley 30 is aligned with thedriven pulley 20.

Also carried by the bench 12 are the primary components of the drive,which are the subject of this invention, the drive being referred to ingeneral by the reference numeral 32. The drive 32 includes a hanger,which is referred to in general by the reference numeral 34.

'The hanger 34 includes an upper horizontal part 36 and a depending part38. The upper horizontal part 36 is provided with an elongated slot 40which opens through the free end of the part 36. The slot 40 receivestwo of the bolts 26 mounting the electric motor 22 on the underside ofthe bench 12. In order to compensate for the mounting of the hanger 34,there is also provided a spacer 42 which corresponds to the horizontalpart 36 and which is provided with an elongated slot 44. The spacer 42is passed over the other two bolts 26 securing the motor 22 in place.

Referring now to Figure 3 in particular, it will be seen that thevertical part 38 of the hanger 34 is provided with a verticallyelongated slot 46. The slot 46 has passed therethrough a bolt 48 whichin turn carries a left, as viewed in Figure 3, by a collar 58 which isretained on the shaft 52 by means of a setscrew 60. The

idler pulley 56 is limited in its movement to the right by means of acam assembly which is referred to in general by the reference numeral62. Thus the idler pulley 56 is maintained in alignment with the drivepulley 30 and the driven pulley 20. It is to be noted that the drivepulley 30 is'disposed intermediate the driven pulley 28 and the idlerpulley 56. It is also to be noted that the proportions of the idlerpulley 56 and the driven pulley as compared to the drive pulley 30 issuch that a drivebelt 64 entrained over the idler pulley 56 and thedriven pulley 20 is normally disposed closely adjacent to, but out ofcontact with the drive pulley 30.

In order to assure the proper freedom of movement of the idler pulley56, it is provided with a bushing 66. Extending through the idler pulley56 and the bushing 66 is a bore 68 which has disposed in the inner partthereof a lubricating wick 70. The outer end of the bore 68 is closed bymeans of a setscrew 72.

The cam assembly 62 is part of a brake which is referred to in generalby the reference numeral 74. The cam assembly 62 includes a female cammember 76 which is retained in place on the shaft 52 by means of asetscrew 78. 'The female cam member 76 also functions as a positioningcollar for the idler pulley 56.

The cam assembly also includes a male cam member 80 which is rotatablyjournaled on the shaft 52. As is best shown in Figure 7, the female cammember 76 is provided in that end thereof which opposes the male cammember 80 with a cam slot '82 in which there is normally seated aprojecting cam member 84 of the male cam member 80.

The right end of the male member 80 is provided with a polygonalcross-sectional extension 86. Engaged on the projection 86 and coupledto the male cam member 80 thereby is an intermediate part of a bellcrank 88. The bell crank 88 is retained on the male cam member 80 bymeans of a thrust washer 90 which bears against both the projection 86and the bell crank 88.

Disposed remote from the thrust washer 96 is a collar 92 which isretained in place on the right end of the shaft 52 by means of asetscrew 94. Extending between the collar 92 and the thrust washer 90 isa spring 96 which retains the bell crank 88 on the projection 86.

through a bore in the arm 100 and which is retained in an adjustedposition by means of nuts 108 and 110 disposed on opposite sides of thearm 100.

Carried by the opposite end of the shaft. 102 in alignment with thedrive belt 64 is a belt tensioning roller 112. The belt tensioningroller 112 is provided with bearings 1'14 mounting it on the shaft 182and to assure the freedom of rotation thereof. The roller 112 ispositioned by means of a collar 116 and a nut 118 disposed at oppositeends thereof.

As is best illustrated in Figures 3 and 4, carried by the male cammember 80 is a brake mounting plate 120 which is generally rectangularin outline. Secured to the brake mounting plate 120 is a pair ofprojecting brake shoes 122. The brake shoes 122 are of a length wherebythe ends thereof engage the idler pulley 56 and prevent rotation thereofwhen the cam assembly 62 is in its inoperative position, as isillustrated in Figure 3. The plate 120 is secured on the male cam member80 by means of a setscrew 124.

The legs 14 at opposite ends of the bench 12 have lower portions thereofconnected together by transverse frame members 126. Extending betweenthe transverse frame members is the longitudinal bar 128. Secured to theright portion of the bar 128 is a hinge-130 which carries a foot pedal132. The foot pedal 132 is connected to the arm 98 by means of the link134.

The connection between the hanger 34 and the support 50 is such that theidler pulley 56 may be properly aligned with respect to the drivenpulley and the drive pulley. 30' whereby the drive belt 64 is disposedclosely adjacent the drive pulley 30, but out of engagement therewith,and at the same time the drive belt 64 is properly tensioned.

It is to be understood that during the general use of the sewing machineconstruction 10, the electric motor 22 will run continuously. When it isdesired to actuate the sewing machine unit 16, the foot pedal 132 isdepressed with the result that the bell crank 88 is pivoted. Thepivoting of the bell crank 88 simultaneously results in the releasing ofthe brake 74 and the movement of the drive belt 64 into engagement withthe drive pulley 38. The brake 74 is released by the rotation of themale cam member which results in the movement of the male cam member 80'to the right. Movement of the .male cam member 80 to theright, ofcourse, results in movement of the brake shoes 122 to the right and outof engagement with the idler pulley 56 so that the idler pulley 56 isfree to rotate.

The pivoting'of the bell crank 88 also results in'the movement of thebelt tensioning roller 112 into engagement with the belt 64 closelyadjacent to the drive pulley 30 and thus the movement of the belt 64into frictional engagement with the drive belt 30. By varying thepressure contact between the drive belt 64 and the drive pulley 30,slippage may be controlled and thus the speed of rotation of the drivenpulley 20 may be controlled. By increasing the downward pressure on thefoot pedal 132, the speed of the sewing machine unit 16 may be increased.as is desired. Furthermore, as soon as the pedal 132 is released, themale cam member 80 will rotate back to its original position at whichtime the brake shoes 122 will again engage the idler pulley 56 immediately stopping the rotation of the idler pulley 56. This, of course,will stop the driving of the drive belt 64 causing the stopping of thesewing machine unit 16..

From the foregoing description of the present invention, it will be seenthat the drive 32 is of such a nature that the response to the actuationthereof by the depressing of the foot pedal 132 is instantaneous.Further, the speed at which the driving machine unit 16 is driven may bereadily varied by the operator of the sewing machine construction 10 bythe pressure exerted on the foot pedal 132. Further, as stated above,when the foot pedal ,132 is released, the driving of the sewing machineunit 16 is immediately discontinued.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly, all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention asclaimed.

What is claimed as new is as follows: 7

1. A drive unit for sewing machines and the like having a driven pulley,said drive unit comprising a fixed power source having a drive pulleyaligned with said driven pulley, an idler pulley disposed in alignmentwith said driven pulley and said drive pulley, said drive pulley beingdisposed intermediate said driven pulley and said idler pulley, a drivebelt entrained over said driven pulley and said idler pulley, at leastone of said driven pulley and said idler pulley being of an effectivediameter larger than the effective diameter of said drive pulley wherebysaid drive belt is normally out of engagement with said drive pulley,means engageable with said drive belt to move said drive belt intodriven engagement with said drive pulley, brake means selectivelymovable into and out of engagement with a side of said idler pulley forstopping overriding movement of said drive belt when said drive beltmoves out of engagement with said drive pulley.

2. A drive unit for sewing machines and the like having a driven pulley,said drive unit comprising a fixed power source having a drive pulleyaligned with said driven pulley, an idler pulley disposed in alignmentwith said driven pulley and said drive pulley, said drive pulley beingdisposed intermediate said driven pulley and said idler pulley, a drivebelt entrained over said driven pulley and said idler pulley, at leastone of said driven pulley and said idler pulley being of an eifectivediameter larger than the effective diameter of said drive pulley wherebysaid drive belt is normally out of engagement with said drive pulley,means engageable with said drive belt to move said drive belt intodriven engagement with said drive pulley, brake means selectivelymovable into and out of engagement with a side of said idler pulley forstopping overriding movement of said drive belt when said drive beltmoves out of engagement with said drive pulley, and a common control forsaid first mentioned means and said brake means.

3. A drive unit for sewing machines and the like having a driven pulley,said drive unit comprising a fixed power source having a drive pulleyaligned with said driven pulley, an idler pulley disposed in alignmentwith said driven pulley and said drive pulley, said drive pulley beingdisposed intermediate said driven pulley and said idler pulley, a drivebelt entrained over said driven pulley and said idler pulley, at leastone of said driven pulley and said idler pulley being of an effectivediameter larger than the effective diameter of said drive pulley wherebysaid drive belt is normally out of engagement with said drive pulley,means engageable with said drive belt to move said drive belt intodriven engagement with said drive pulley, brake means releasablyconnected to said idler pulley at the side thereof for stoppingoverriding movement of said drive belt when said drive belt moves out ofengagement with said drive pulley.

4. A drive unit for sewing machines and the like having a driven pulley,said drive unit comprising a fixed power source having a drive pulleyaligned with said driven pulley, an idler pulley disposed in alignmentwith said driven pulley and said drive pulley, said drive pulley beingdisposed intermediate said driven pulley and said idler pulley, a drivebelt entrained over said driven pulley and said idler pulley, at leastone of said driven pulley and said idler pulley being of an effectivediameter larger than the effective diameter of said drive pulley wherebysaid drive belt is normally out of engagement with said drive pulley,means engageable with said drive belt to move said drive belt intodriven engagement with said drive pulley, brake means releasablyfrictionally connected to said idler pulley at one side thereof forstopping overriding movement of said drive belt when said drive beltmoves out of engagement with said drive pulley, and a common control forsimultaneous but opposite operation of said first mentioned means andsaid brake means.

5. A drive unit for sewing machines and the like having a driven pulley,said drive unit comprising a fixed power source having a drive pulleyaligned with said driven pulley, an idler pulley disposed in alignmentwith said driven pulley and said drive pulley, said drive pulley beingdisposed intermediate said driven pulley and said idler pulley, a drivebelt entrained over said driven pulley and said idler pulley, at leastone of said driven pulley and said idler pulley being of an effectivediameter larger than the effective diameter of said drive pulley wherebysaid drive belt is normally out of engagement with said drive pulley, abelt tensioning roller disposed adjacent said drive pulley andengageable with said outer surface of said drive belt, and meansconnected to said belt tensioning roller for moving said belt tensioningroller into frietional engagement with said drive belt and said drivebelt into frictional engagement with said drive pulley, brake meansselectively movable into and out of engagement with a side of said idlerpulley for stopping overriding movement of said drive belt when saiddrive belt moves out of engagement with said drive pulley.

6. .A drive unit for sewing machines and the like having a drivenpulley, said drive unit comprising a fixed power source having a drivepulley aligned with said driven pulley, an idler pulley disposed inalignment with said driven pulley and said drive pulley, said drivepulley being disposed intermediate said driven pulley and said idlerpulley, a drive belt entrained over said driven pulley and said idlerpulley, at least one of said driven pulley and said idler pulley beingof an effective diameter larger than the effective diameter of saiddrive pulley whereby said drive belt is normally out of engagement withsaid drive pulley, a belt tensioning roller disposed adjacent said drivepulley and engageable with said outer surface of said drive belt, andmeans connected to said belt tensioning roller for moving said belttensioning roller into frictional engagement with said drive belt andsaid drive belt into frictional engagement with said drive pulley, brakemeans selectively movable into and out of engagement with a sideof saididler pulley for stopping overriding movement of said drive belt whensaid drive belt moves out of engagement with said drive pulley, meansco'nnecting said first mentioned means to said brake means forcontrolling the operation of said brake means.

7. A drive unit for sewing machines and the like having a driven pulley,said drive unit comprising a fixed power source having a drive pulleyaligned with said driven pulley, an idler pulley disposed in alignmentwith said driven pulley and said drive pulley, said drive pulley beingdisposed intermediate said driven pulley and said idler pulley, a drivebelt entrained over said driven pulley and said idler pulley, at leastone of said driven pulley and said idler pulley being of an eflfectivediameter larger than the effective diameter of said drive pulley wherebysaid drive belt is normally out of engagement with said drive pulley, abelt tensioning roller disposed adjacent said drive pulley andengageable with an outer surface of said drive belt, and means connectedto said belt tensioning roller for moving said belt tensioning rollerinto frictional engagement with said drive belt and said drive belt intofrictional engagement with said drive pulley, brake means engaged withsaid idler pulley and including a pair of axially extending frictionplates movable axially into engagement with one side of said idlerpulley for stopping overriding movement of said drive belt when saiddrive belt moves out of engagement with said drive pulley.

8. A drive unit for sewing machines and the like having a driven pulley,said drive unit comprising a fixed power source having a drive pulleyaligned with said driven pulley, an idler pulley disposed in alignmentwith said driven pulley and said drive pulley, said drive pulley beingdisposed intermediate said driven pulley and said idler pulley, a drivebelt entrained over said driven pulley and said idler pulley, at leastone of said driven pulley and said idler pulley being of an effectivediameter larger than the effective diameter of said drive pulley wherebysaid drive belt is normally out of engagement with said drive pulley, abelt tensioning roller disposed adjacent said drive pulley andengageable with an outer surface of said drive belt, and means connectedto said belt tensioning roller for moving said belt tensioning rollerinto frictional engagement with said drive belt and said drive belt intofrictional engagement with said drive pulley, brake means engaged withsaid idler pulley for stopping overriding movement of said drive beltwhen said drive belt moves out of engagement with said drive pulley,means connecting said first mentioned means to said brake means forcontrolling the operation of said brake means.

9. The combination of claim 1 wherein said brake means is directlyengageable with a side of said idler pulley upon diametrically oppositeportions thereof.

10. The combination of claim 1 including an axle upon 7 '3' which saididler pulley is rotatably journaled, said brake means including a membermovable axially upon said axle and having po'rtions directly engageablewith a side 9 of said idler pulley.

11. The combination of claim 1 including an axle upon which said idlerpulley is rotatably journaled, said brake means including a membermovable rotationally upon said axle and having portions directlyengageable with a side of said idler pulley, said first means includinga lever mounted on said member and rotatable in unison therewith, meansfor actuating said lever.

12. The combination of claim 1 including an axle upon which said idlerpulley is rotatably journaled, said brake means including a membermovable rotationally upon said axle and having portions directlyengageable with at with a side of said idler pulley, said portionscomprising plates on opposite sides of said axle engageable with theside of said idler pulley. I p

1 4. The combination of claim 1 including an axle upon which said idlerpulley is rotatably journaled, said brake means including a membermovable upon said axle and having portions directly engageable with aside of said idler pulley, said first means including a lever mounted onsaid member and rotatable in unison therewith, means for actuating saidlever, and a belt tensioning roller journaled on said lever and directlyengageable with said belt, said lever having a cantilever shaftprojecting laterally to one side thereof, said tensioning roller beingjournaled on said shaft and extending into alignment with said belt,driving and driven pulleys.

References Cited in the file of this patent UNITED STATES PATENTS656,853 Noble Aug. 28, 1900 1,301,849 Jones Apr. 29, 1919 2,195,229Smart Mar. 26, 1940 2,739,552 Sailer Mar, 27, 1956

